Question

Assertion-Absolute zero is a theoretically possible temperature at which the volume of the gas becomes zero.
Reason: The total kinetic energy of the molecule is zero at this temperature.
A)Both assertion and reason are correct and the reason is the correct explanation of the assertion.
B)Both assertion and reason are correct and the reason is not the correct explanation of the assertion.
C)Assertion is correct but the reason is incorrect
D)Assertion is incorrect but the reason is correct
E)Both assertion and reason are incorrect

Answer 1

Hint:To answer this question, you should recall the concept of properties of materials at absolute zero temperature. It is defined as the lowest possible temperature where nothing could be colder and no heat energy remains in a substance. At this temperature the fundamental particles of nature have minimal vibrational motion, retaining only quantum mechanical, zero-point energy-induced particle motion.

Complete Step by step solution:
We know that an “ideal gas” at constant pressure would reach zero volume at a temperature known as the absolute zero. Although, any real gas would condense to a liquid or a solid at a temperature higher than absolute zero; therefore, the ideal gas law is only an approximation to real gas behaviour. From the definition of absolute zero, we know that it is the theoretical point where all molecular motion ceases and they are at complete rest. Also as per kinetic theory, there should be no movement of individual molecules at absolute zero, so any material at this temperature would be solid. As both, the assertion and reason are correct statements but the reason does not correctly explain the assertion.
Therefore, we can conclude that the correct answer to this question is option B

Note: At 'higher temperature' and 'lower pressure', a gas behaves like an ideal gas, as the potential energy due to intermolecular forces becomes less significant compared with the particles' kinetic energy, and the size of the molecules becomes less significant compared to the space between them. In other words, the Vander Waal constants a and b which are used in the real gas equation, become zero and the equation gets converted to the ideal gas equation.